Heating device for aerosol dispenser



June Z8, 1966 y J. E. AYREs ETAL 3,258,170

HEATING DEVICE FOR AEROSOL DISPENSER Filed April l5, 1964 3 Sheets-Sheet l :1f-2@- 35 3 -i1 1B| 3 34 11B 2 9-" g5 537* 23:35- 26 5:33- 30 24 1A|16 2g f |1A i l i g1 20 7 wz INVENTORS June 28, 1966 J. E. AYREs ETAL HEATING DEVICE FOR AEROSOL DISPENSER 3 Sheets-Sheet 2 Filed April 13, 1964 INVENTORS JOHN E AYRES IRVING REICH ROBERT G. FOURMAN BV @ahw AGENT June 28, 1966 J. E. AYREs ETAL HEATING DEVICE FOR AEROSOL DISPENSER 3 Sheets-Sheet 5 Filed April l5. 1964 M M R m@ w NRWF EY! VAMMG 'NIL T GR NNE www JRR AGENT United States Patent O 3 258 170 HEATING DEVICE liOR AEROSOL DISlENSER John E. Ayres, Mountain Side, and Irving Reich, Princeton, and Robert G. Fourman, East Brunswick, NJ., assignors to Carter-Wallace, Inc., a corporation of Mar land y Filed Apr. 13, 1964, Ser. No. 358,989

8 Claims. (Cl. 222-146) The present invention relates in general'to devices for preparing and dispensing aerosol lathers 1n heated c ondition. More particularly, this invention relates to improved devices which are capable of heating such lathers with high efficiency.

In recent years, pressurized aerosol products, such as shaving cream lathers, shampoo lathe'rs., and the like, have been gaining widespread recognition. More .recently, a number of devices which permit the dispensing of such products in a heated condition have been described. l

The advantages which can be derived by the use of such latter devices are especiallyobvious when such devices are used in conjunction with aerosol shaving lathers; therefore, the present invention will be described with particular reference to containers for preparing and dispensing aerosol shaving lathers, but it should-be evident from the following description that the devices of the present invention are suitable for use in conJunction with a number of aerosol products, such as lather shampoos, and like.

Aerosol shaving lathers are usually produced from liquid compositions comprising a mixture of an aqueous .soap or detergent solution and a liqueiield normallygaseous propellant. Such compositions, when released from a valve-controlled aerosol type container yield a stable lather which can be directly applied to the skin of the user prior to shaving. Due to the cooling effect exerted by the expansion and evaporation of the liquefied propellant the temperature of such lather is usually below room temperature and the body temperature of the user. The application of such cool lather to the body of the user is not entirely pleasant. Furthermore the softening effect of such lather on the beard or hair of the user is reduced by the lower temperature thereof.

The desirability of providing a heated aerosol shaving lather has been recently recognized and a number of devices have been proposed in the art to perform such function. Such prior devices, however, have been generally ine'icient and cumbersome and have failed to provide a simple, practical and economical way to solve the proposed probelm.

Some of the proposed devices utilize electrical means for heating a long tube through which the lather product passes after release from the aerosol container. Such use of electrical heating means introduces the hazards and inconvenience of fires and electric cords.

Other similar devices which have been proposed utilize a heating jacket around a lather discharge tube, said heating jacket being connected to a hot water tap and being supplied with a continuous flow of hot water therefrom. Due to the low heat transfer coefficients inherent to such lathers, such devices are ineffective in raising the product to temperatures substantially close to the hot water tap temperature unless a lather discharge tube of substantial length is used. The use of such long tubes results in a breakdown of the lather due to the considerable flow resistance offered by such tubes and to the long residence time. IFurthermore, a substantial Volume of lather is left within the tube after the user discontinues the operation. This residual lather, in a compressed state due to the high flow resistance of the device, will expand and ooze 3,258,170 Patented June 28, 1966 out of the tube outlet causing prolonged and copious afterliow.

More recently, a device has been proposed in an attempt to eliminate some of the disadvantages of the prior art devices. Such proposed device comprises a cylindrical heat-conductive chamber of sheet metal projecting in exposed position from a standard aerosol-type container and containing therein a supply of heat-conductive material, such as steel wool. The proposed mode of operation involves heating the cylindrical chamber, and any liquid lather-forming material contained therein, by holding said chamber in contact with hot water and thereafter discharging the heated liquid as a warm lather. The proposed device solves to a certain extent one of the prior art problems, namely the necessity of heating rather large volumes of lather after extrusion, by heating instead the relatively smaller volume of corresponding liquid prior to extrusion. In practice, however, a number of shortcomings, which shall hereinafter become apparent in the light of the instant invention, are inherent to the proposed device.

It is an object of the present invention to provide a device for preparing and `dispensing heated aerosol foams. It is a further object of the invention to provide an iniproved device for preparing and dispensingheated shaving lathers, said device eliminating one or more of the disadvantages of the prior art. These and other objects will become apparent to those skilled in the art in the light of the instant specification.

In a broad aspect, the present invention relates to a device for preparing and dispensing heated aerosol foams from an aerosol-type container provided with anoutlet member and containing therein a mixture of an aqueous soap solution and a liquefied normally-gaseous propellant, said device comprising a heat-conductive chamber having an inlet member interconnected with the outlet member of said container; means mounted within said chamber for preventing uid flow from said chamber to said container; an outlet member having a manually-operated discharge valve for dispensing the contents for use; and heating means on said heat-conductive chamber for heating the contents thereof.

An essential feature of the device of .the present invention is the introduction of means within the heat-conductive chamber for preventing fluid flow from said chamber to the container. Such means serve to prevent .the return of any portion of the liquid soap solution, upon its expansion due to heating, from the heat-conductive chamber to the container. This back-flow, which is inherent lto previously-proposed devices which operate by heating the soap solution in its liquid form, and its undesirable effects, will be discussed in detail in conjuncti-on with lthe description of the devices of the present invention.

These and other objects will be best understood from the following description of preferred devices of the invention, selected for the purpose of illustration and not of limitation, and shown in the accompanying drawings.

Referring to the drawings:

FIG. 1 is a side elevational view of a preferred device, partly in longitudinal section;

FIG. 1A is a sectional view taken along the line 1A-1A of FIG. 1.

FIG. 1B is a sectional view taken along the li-ne 1B-1B of FIG. 1.

With continuing reference to the accompanying drawings, yFIG. 1 shows a preferred form of a heating device of the invention removably mounted on a standard aerosol container of -a type commercially used by'some manufacturers of aerosol products. It is `comprised of can 10 having a suitable attached bottom, not shown in the drawing, and lid 11. Lid 11 is provided with a container outlet member consisting `of a central opening for discharge of product, said opening being provided with manuallyoperated valve means.

The valve means include a diaphragm 12, preferably made of rubber or other resilient material, which is mounted between the lid 11 and the conventional dip tube 13. The diaphragm 12 includes a plurality of openings 14 Which are normally closed by -the centrally located depending tubular portion 15 of lid 11. For normal usage, such laerosol containers are provided with a valve actuator assembly, not shown in the drawing, which consists of a Valve button, a dispensing spout, and a tubular valve actuator extending downwardly from said valve button. Customarily, the user manually depresses the valve button, displacing the tubular valve actuator downwardly in actuating contact with the diaphragm 12. When the diaphragm is thus depressed, the openings 14 are no longer obstructed by the `tubular portion 15 and the pressurized product is discharged from the can through said openings and thence through the dispensing spout of said valve actuator assembly. In the practice of the present embodiment of the invention, the valve actuator assembly, which is customarily mounted with a friction `tit coaxially with the opening in lid 11, is removed prior yto mounting Athe heating device of the invention on the aerosol container.

The valve construction described above is conventional and it will be understood, of course, that other and different forms of valve mechanisms may be employed with the present invention. It will also be understood that the use of such different valve mechanism will necessitate some minor changes in the construction of the novel heating device, but the necessity of such changes and the exof stiffness, lightness and low rate of heat conduction,

such as-linear polyethylene, polypropylene, polystyrene, and the like.

The bottom of cup 16 is fashioned with a configuration generally complementary to the top of the aerosol package and includes a depending peripheral annular ange 17 provided with an internal annular channel 18 to iirmly engage the upper rim 19 of the package with a friction snap-tit.

Extending downwardly from cup 16 is centrally located tubular valve actuator 20 having an internal passageway 21 extending therethrough. When the heating device is mounted on the package by exerting downward pressure sufficient to snap annular flange 17'over rim 19, the tubular actuator 20 is similarly displaced downwardly with a friction iit through the tubular opening deiined by the depending tubular portion of the lid 11. The lower end of the actuator, provided with a diametrically disposed slot 22, engages diaphragm 12, actuating said diaphragm and thereafter maintaining it in the open position, i.e., in the position wherein openings 14 are no longer obstructed by tubular portion 15. Diaphragm 12 remains in saidopen position as long as the heating device is mounted on the aerosol package.

Fixedly mounted within body 16 and extending upwardly into the cup defined by said body is a centrally located cylindrical body 23 having tubular arms 24 and 25 extending radially therefrom and forming an integral part thereof. -For optimum eiiciency, said tubular arms are positioned on cylindrical body 23 at points substantially removed from each other.

Mounted within body 16 a` heat-conductive chamber is provided for holding the desired amount of liquid soap solution. In the illustrative embodiment shown, the heatconductive chamber is defined by a radiator consisting of two closely spaced upright cylindrical plates 26 and 27,

The top and bottom edges of cylindrical metal plates 26 and 27 are sealed to one another by conventional means to provide a pressure-tight upright -chamber 28 of annular cross-section. The radiator is formed from a heat-conduc-tive material, preferably metal, and is constructed as to be capable of withstanding pressures in the range of up to p.s.i. which are generated during operation of the present device, which operation will be explained in detail hereinafter.

As best shown in- FlG. 1A, the radiator is connectively sealed to tubular arm 24 and the chamber thereof is interconnected With the container outlet member by means of a chamber inlet member comprising passageway 29, which extends Ithrough tubular arm 24 and cylindrical body 23, and passageway 21, which extends through valve actuator 20 and is interconnected with said passageway 29. Located in passageway 29 is check valve 30, positioned so as to allow the liquid soap solution to flow from the container through passageway 29 and into chamber 28 but as to prevent any uid from returning from chamber 28 to the container. Such backflow, which would occur because of gravity iiow and of the pressure dilferential which develops between chamber 28 and the interior of container 10 when the chamber is heated, is hereby prevented.

Similarly, at a poin-t in the -chamber substantially removedv from said inlet conduit means, the radiator has outlet conduit means connectively sealed to tubular arm 25. Passageway 31 extends through tubular arm 25 and interconnects chamber 28 with valve chamber 32. Such embodiment is best shown in FIG. 1B.

Located on Valve chamber 32 and secured to cylindrical body 23 by crimping .the outer edges of the closure member 33 over a bead which surrounds the valve chamber opening in the top of body 23, is diaphragm 34. Said diaphragm, which includes a plurality of openings 35 which are normally closed by the depending tubular portion 36 of closure member 33, is similar in construction and in mode of operation to diaphragm 12 hereinefore described.

vMounted on cylindrical body 23 and secured -thereto by a friction :it,is valve actuator assembly 36 comprising valve button 37, dispensing spout 38 and tubular valve actuator 39. When the user manually depresses valve button 37, tubular valve actuator is displaced downwardly into actuating contact with diaphragm 34. Any pressurized product present in chamber 28 is thus discharged from said chamber through openings 35 and then through a chamber outlet member, i.e., through longitudinal groove 40 and thence to the atmosphere through passageway 41 in dispensing spout 38.

The illustrated heating device also comprises an annular top portion 42 which is fitted to the top of body 16.

In operating this device of the invention, the user, after removing the standard valve actuator assembly from a commercial container of aerosol shaving lather, mounts the heater on said container by displacing the unit downwardly as to allow peripheral annular flange 17 to engage 4the upper rim 19 of the container. Tubular valve actuator 20 comes into actuating contact with diaphragm 12, allowing the pressurized contents of the vpackage to iiow through openings 14 and to till chamber 28.

The user then places the device under a hot water faucet and -ills body 16 with hot water. The hot water submerges the radiator, heating the radiator walls to substantially the temperature of the water itself. At the same time, 4the liquid soap solution which is present in chamber 28 is similarly heated by heat conduction 'through said radiator walls.

Upon heating, due to the increase in vapor pressure of the propellant which is present in chamber 28, pressures of up to about 150 p.s.i.g. develop in said chamber. Such pressures are substantially higher than the pressures prevailing in container 10. However, contrary to prior art devices, check Valve 30 prevents the heated soap solution from escaping from chamber 28 back into container 10, thereby making i-t possible to maintain said soap solution in heat-exchange relationship with the heated radiator walls for a time suicient for said solution to reach a temperature substantially approximately the wall temperature.

Having removed the device from under the faucet, the user presses actuator button 37 which in turn opens diaphragm 34 as shown in FIG. 1. The heated product from chamber 28 is propelled through the multiple openings 35 and thence through passageways 40 and 41 and out yof spout 38. In the meantime, due to the pressure decrease in chamber 28, cold soap solution from container is propelled upwardly through dip tube 13 and thence through passageways 21 and 29, past check valve 30, to till chamber .28. The new charge of liquid soap solution remains in chamber 28 until such time as the user wishes to use the device again. The check valve serves to segregate the charge and lto prevent it from returning to container 10 by gravity flow, as would normally occur on storage.

In a particularly preferred aspect of the invention, such upward surge of the cold soap solution from container 10 into chamber 28 is facilitated by providing, in said.

container, in addition to the standard liqueiied normallygaseous propellant, which is customarily used in pressurized aerosol products, an inert substantially water-insoluble gas which, due to its physical properties, will exist in the gaseous state under the conditions prevailing in said container. It has been found that the use of such gas which, due to its insolubility in the aqueous soap solution and to its ability to remain in the gaseous phase,'makes it possible to lill chamber 28 to its maximum capacity with liquid soap solution, as explained hereinafter.

Such gas, which is preferably nitrogen but which can be any inert gas substantially insoluble in the aqueous soap solution and substantially non-liqueliable under the conditions prevailing in the aerosol container, such as air, oxygen, and the like, is preferably used in an amount sutiicient to provide a gaseous phase in said container in which the inert substantially water-insoluble gas has a partial pressure of from about 10 to about 50 p.s.i.g. at 70 F. A total container pressure in the range of from about to about 85 p.s.i.g. at 70 F. is preferred.

In the absence of such inert, insoluble, non-liquefied gas, the liquid in the container does not completely fill the heating chamber. Especially when the heating chamber is warmer than the bulk of the liquid in the container,

solution which enters the chamber tends to partially vaporize so that the chamber becomes lled not with the liquid but with a foamy mixture comprising substantial quantities of vaporized propellant suspended in the liquid as bubbles. The presence of such bubbles reduces the amount of liquid soap available in the chamber and at the same time causes the formation of an undesirably soft and somewhat unstable foam upon extrusion.

On the other hand, when an inert, insoluble, nonliqueed gas is present, it serves to force the liquid up into the heating chamber under a positive head of pressure and to ensure that the liquid in the chamber is maintained under pressure in excess of the vapor pressure of the liquefied propellant, thus causing the chamber to become filled completely with liquid containing no gas spaces or bubbles.

The foregoing description is illustrative of the construction and operation of a preferred embodiment of the present invention. Other embodiments should be evident to those skilled in the art in the light of the instant disclosure, without departing from the spirit and scope of the invention.

For example, it should be evident that the shape of the heating chamber is not critical and that a coiled tube or the like can be substituted for the radiator of the illustrated embodiment. In another aspect of the invention the heating chamber can be externally mounted and heated by contact with hot running Water from the faucet, rather than by intimate prolonged contact with a captive body of hot water.

Additionally, it should be evident that the heat-conductive chamber can be constructed as to be permanently aixed to the aerosol container.

What is claimed is:

1. A device for preparing and dispensing heated aerosol foams from an aerosol-type container provided with an outlet member having an openl position and a closed position and containing therein a mixture of an aqueous soap solution and a liquefied normally-gaseous propellant, said device comprising a heat-conductive chamber having an inlet member interconnected with the outlet member of said container, means on said inlet member for maintaining said outlet member in the open position, means mounted within said inlet member for preventing uid flow from said chamber to said container, and an outlet member having a manually-operated discharge valve for dispensing the contents for use; and means whereby said heat-conductive chamber may be heated by immersion in hot water.

2. The device of claim 1 wherein the container contains a gaseous phase comprising an inert substantially water-insoluble gas at a partial pressure of from about l0 to about 50 p,s.i.g. at 70 F.

3. A device for preparing and dispensing heated aerosol foams from an aerosol-type container provided with an outlet member having an open position and a closed positionaand containing therein a mixture of an aqueous soap solution and a liquefied normally-gaseous propellant, said device comprising a heat-conductive chamber having an inlet member interconnected with the outlet member of said container, means on said inlet member for maintaining said outlet member in the open position, means mounted within said inlet member for preventing liuid flow from said chamber to said container, and an outlet member having a manually-operated discharge valve for dispensing the contents for use; and a body capacitated to hold a supply of hot water in heat' exchange relation with said heat-conductive chamber.

4. The device of claim 3 wherein the container contains a gaseous phase comprising an inert substantially water-insoluble gas at a partial pressure of from about l0 l to about 50 p.s.i.g. at 70 F.

5. A device for preparing and dispensing heated aerosol foams from an aerosol-type container provided. with an outlet member having an open position and a closed position and containing therein a mixture of an aqueous soap solution and a liquefied normally-gaseous propellant, said device comprising a heat-conductive chamber having an inlet member interconnected with the outlet member of said container, means on said inlet member for maintaining said outlet member in the open position, a check valve mounted within said inlet member as to permit fluid ow from said container to said chamber but as to prevent liuid ow from said chamber to said container, and an outlet member having a manually-operated discharge valve for dispensing the contents for use; and means whereby said heat-conductive chamber may be heated by immersion in hot water.

6. The device of claim 5 wherein a container contains a gaseous phase comprising an inert substantially waterinsoluble gas at a partial pressure of from about 10 to about 50 p.s.i.g. at 70 F.

7. A device for preparing and dispensing heated aerosol foams from an aerosol-type container provided With an outlet member having an open position and a closed position and containing therein a mixture of an aqueous soap solution and a liquefied normally-gaseous propellant, said device comprising a heat-conductive chamber having -an inlet member interconnected with the outlet member of said container, means on said inlet member for maintaining said outlet member in the open position, a check valve mounted Within said inlet member as to permit fluid 7 8 flow from said container to-sai-d chamber but -as to prevent References Cited by the Examiner uid flow from said chamber to said container, and an i outlet member having a manually-operated discharge valve UNITED STATES PATENTS for dispensing the contents for use; and a body capacitated 2,873,351 2/ 1959 Lannert 219-214 to. hold a supply of hot Water in heat exchange relation 5 3 043 484 7 /1962 Jouy. with said heat-conductive chamber.

8. The device of claim 7 wherein the container contains EVON BLUNK, primary Examiner. a gaseous phase comprising an inert substantially Waterinsoluble gas at a partial pressure of from about 10 to ROBERT B- REEVES,` LOUIS DEMBO, F- R- HAN- about 50 p.s.i.g. at 70 F. DREN, AAssistant Examiners. 

1. A DEVICE FOR PREPARING AND DISPENSING HEATED AEROSOL FOAMS FROM AN AEROSOL-TYPE CONTAINER PROVIDED WITH AN OUTLET MEMBER HAVING AN OPEN POSITION AND A CLOSED POSITION AND CONTAINING THEREIN A MIXTURE OF AN AQUEOUS SOAP SOLUTION AND A LIQUEFIED NORMALLY-GASEOUS PROPELLANT, SAID DEVICE COMPRISING A HEAT-CONDUCTIVE CHAMBER HAVING AN INLET MEMBER INTERCONNECTED WITH THE OUTLET MEMBER OF SAID CONTAINER, MEANS ON SAID INLET MEMBER FOR MAINTAINING SAID OUTLET MEMBER IN THE OPEN POSITION, MEANS MOUNTED WITHIN SAID INLET MEMBER FOR PREVENTING FLUID FLOW FROM SAID CHAMBER TO SAID CONTAINER, AND AN OUTLET MEMBER HAVING A MANUALLY-OPERATED DISCHARGE VALVE FOR DISPENSING THE CONTENTS FOR USE; AND MEANS WHEREBY SAID HEAT-CONDUCTIVE CHAMBER MAY BE HEATED BY IMMERSION IN HOT WATER. 